For the past few weeks I've noticed these unusual colored lines/artifacts appearing where my cursor should be when using Adobe InDesign. I've also experienced similar issues occasionally looking at my exported InDesign projects in Preview, with purple/green lines or blocks of color appearing across the app window.
From what I've read online this could be symptoms of a GPU failure, but this only happens in InDesign. For the record, this is happening on a mid-2012 13" MBP, so it's an integrated Intel HD 4000 GPU.